Pregnant women diagnosed with COVID-19 are at significantly higher risk of giving birth prematurely, with data showing that a quarter of such expectant mothers with the disease delivered early, according to a Turkish expert.

Merih Cetinkaya, a professor at the University of Health Sciences in Istanbul, told Anadolu Agency (AA) that the delta variant of the virus has been having a pronounced effect on pregnant women.

Cetinkaya said there had been a significant rise in the numbers of pregnant women who were admitted to intensive care and/or lost their lives due to the virus.

Babies born to mothers admitted to intensive care units with severe COVID-19 also tend to stay in the hospital for longer after birth, Cetinkaya added, noting that the Health Ministry had called on all pregnant women in Turkey to get vaccinated as soon as possible.

"COVID-19 causes premature birth," he said. "There have been many studies on premature births after the pandemic around the world," he said. The global average of preterm births is around 11%, meaning expectant mothers affected by COVID-19 are more than twice as likely to give birth early.

Citing a new study published in a scientific journal in the U.S., he said: "We observe this in our own (hospital) services as well. According to the latest study, one out of every four pregnant women who contract the coronavirus gives birth prematurely."

Noting that studies have shown that the immunosuppressive status of pregnant women is higher than other individuals, Cetinkaya said pregnant women should still not avoid going to the hospital because of fears about the coronavirus. "They should have their check-ups on time, get their vaccinations, eat healthily, increase physical activity and remain absolutely isolated."

Pointing out that breast milk protects against COVID-19 and many other diseases, he said: "Mothers who are vaccinated during pregnancy or who have had COVID-19 pass on protective antibodies to the baby through breast milk."

"Even if the mother has the coronavirus, she must wear her mask, pay attention to her hygiene, and should breastfeed her baby," he added.

On Thursday, Turkey recorded 22,234 new COVID-19 cases, 226 deaths, and 29,538 recoveries.

Since December 2019, the pandemic has claimed over 5.13 million lives in at least 192 countries and regions, with more than 256.26 million cases reported worldwide, according to Johns Hopkins University.